Question

The diameter of a circular metallic sheet is 2.1m.Find out its circumference and area

Answer 1

Circumference formula = 2pi r
find the value of r by solving this formula
then area=pir square

Answer 2

circumference = 2 $\pi$ r
                        = 2 x 22 / 7 x 2.1
                       = 13.2 cm

area of the circle = $\pi$r^2
                            = 22/7 x 2.1 x 2.1
                            =13.86 cm^2